V8 fixes

interface/resources/serverless/Scripts/activator-doppleganger.js

@@ -1,4 +1,4 @@
-'use strict';
+'no use strict';
 //
 //  activator-doppleganger.js
 //
@@ -23,6 +23,8 @@
         autoUpdate: true
     });
 
+    // V8TODO: does this need to be fixed? Right now it refers to global object in non-strict mode,
+    // and in strict mode it's undefined
     this.preload = function(entityID) {
        thisEntityID = entityID;
     }

interface/src/scripting/WindowScriptingInterface.cpp

@@ -77,6 +77,7 @@ WindowScriptingInterface::~WindowScriptingInterface() {
 }
 
 ScriptValue WindowScriptingInterface::hasFocus() {
+    Q_ASSERT(engine);
     return engine()->newValue(qApp->hasFocus());
 }
 
@@ -105,6 +106,7 @@ void WindowScriptingInterface::alert(const QString& message) {
 /// \param const QString& message message to display
 /// \return ScriptValue `true` if 'Yes' was clicked, `false` otherwise
 ScriptValue WindowScriptingInterface::confirm(const QString& message) {
+    Q_ASSERT(engine);
     return engine()->newValue((QMessageBox::Yes == OffscreenUi::question("", message, QMessageBox::Yes | QMessageBox::No, QMessageBox::Yes)));
 }
 
@@ -114,6 +116,7 @@ ScriptValue WindowScriptingInterface::confirm(const QString& message) {
 /// \return ScriptValue string text value in text box if the dialog was accepted, `null` otherwise.
 ScriptValue WindowScriptingInterface::prompt(const QString& message, const QString& defaultText) {
     QString result = OffscreenUi::getText(nullptr, "", message, QLineEdit::Normal, defaultText);
+    Q_ASSERT(engine);
     auto sResult = engine()->newValue(result);
     if (sResult.equals(engine()->newValue(""))) {
         return engine()->nullValue();
@@ -232,6 +235,7 @@ ScriptValue WindowScriptingInterface::browseDir(const QString& title, const QStr
     if (!result.isEmpty()) {
         setPreviousBrowseLocation(QFileInfo(result).absolutePath());
     }
+    Q_ASSERT(engine);
     return result.isEmpty() ? engine()->nullValue() : engine()->newValue(result);
 }
 
@@ -276,6 +280,7 @@ ScriptValue WindowScriptingInterface::browse(const QString& title, const QString
     if (!result.isEmpty()) {
         setPreviousBrowseLocation(QFileInfo(result).absolutePath());
     }
+    Q_ASSERT(engine);
     return result.isEmpty() ? engine()->nullValue() : engine()->newValue(result);
 }
 
@@ -323,6 +328,7 @@ ScriptValue WindowScriptingInterface::save(const QString& title, const QString&
     if (!result.isEmpty()) {
         setPreviousBrowseLocation(QFileInfo(result).absolutePath());
     }
+    Q_ASSERT(engine);
     return result.isEmpty() ? engine()->nullValue() : engine()->newValue(result);
 }
 
@@ -373,6 +379,7 @@ ScriptValue WindowScriptingInterface::browseAssets(const QString& title, const Q
     if (!result.isEmpty()) {
         setPreviousBrowseAssetLocation(QFileInfo(result).absolutePath());
     }
+    Q_ASSERT(engine);
     return result.isEmpty() ? engine()->nullValue() : engine()->newValue(result);
 }
 

libraries/avatars/src/AvatarData.cpp

@@ -2557,6 +2557,7 @@ QDataStream& operator>>(QDataStream& in, AttachmentData& attachment) {
 void AttachmentDataObject::setModelURL(const QString& modelURL) {
     AttachmentData data = scriptvalue_cast<AttachmentData>(thisObject());
     data.modelURL = modelURL;
+    Q_ASSERT(engine);
     thisObject() = engine()->toScriptValue(data);
 }
 
@@ -2567,6 +2568,7 @@ QString AttachmentDataObject::getModelURL() const {
 void AttachmentDataObject::setJointName(const QString& jointName) {
     AttachmentData data = scriptvalue_cast<AttachmentData>(thisObject());
     data.jointName = jointName;
+    Q_ASSERT(engine);
     thisObject() = engine()->toScriptValue(data);
 }
 
@@ -2577,6 +2579,7 @@ QString AttachmentDataObject::getJointName() const {
 void AttachmentDataObject::setTranslation(const glm::vec3& translation) {
     AttachmentData data = scriptvalue_cast<AttachmentData>(thisObject());
     data.translation = translation;
+    Q_ASSERT(engine);
     thisObject() = engine()->toScriptValue(data);
 }
 
@@ -2587,6 +2590,7 @@ glm::vec3 AttachmentDataObject::getTranslation() const {
 void AttachmentDataObject::setRotation(const glm::quat& rotation) {
     AttachmentData data = scriptvalue_cast<AttachmentData>(thisObject());
     data.rotation = rotation;
+    Q_ASSERT(engine);
     thisObject() = engine()->toScriptValue(data);
 }
 
@@ -2597,6 +2601,7 @@ glm::quat AttachmentDataObject::getRotation() const {
 void AttachmentDataObject::setScale(float scale) {
     AttachmentData data = scriptvalue_cast<AttachmentData>(thisObject());
     data.scale = scale;
+    Q_ASSERT(engine);
     thisObject() = engine()->toScriptValue(data);
 }
 
@@ -2607,6 +2612,7 @@ float AttachmentDataObject::getScale() const {
 void AttachmentDataObject::setIsSoft(bool isSoft) {
     AttachmentData data = scriptvalue_cast<AttachmentData>(thisObject());
     data.isSoft = isSoft;
+    Q_ASSERT(engine);
     thisObject() = engine()->toScriptValue(data);
 }
 

libraries/script-engine/src/AssetScriptingInterface.cpp

@@ -73,6 +73,7 @@ void AssetScriptingInterface::uploadData(QString data, const ScriptValue& callba
     auto upload = DependencyManager::get<AssetClient>()->createUpload(dataByteArray);
 
     Promise deferred = makePromise(__FUNCTION__);
+    Q_ASSERT(engine);
     auto scriptEngine = engine();
     deferred->ready([=](QString error, QVariantMap result) {
         auto url = result.value("url").toString();
@@ -96,6 +97,7 @@ void AssetScriptingInterface::setMapping(QString path, QString hash, const Scrip
     auto handler = jsBindCallback(thisObject(), callback);
     auto setMappingRequest = assetClient()->createSetMappingRequest(path, hash);
     Promise deferred = makePromise(__FUNCTION__);
+    Q_ASSERT(engine);
     auto scriptEngine = engine();
     deferred->ready([=](QString error, QVariantMap result) {
         jsCallback(handler, scriptEngine->newValue(error), result);
@@ -133,6 +135,7 @@ void AssetScriptingInterface::downloadData(QString urlString, const ScriptValue&
     auto assetRequest = assetClient->createRequest(hash);
 
     Promise deferred = makePromise(__FUNCTION__);
+    Q_ASSERT(engine);
     auto scriptEngine = engine();
     deferred->ready([=](QString error, QVariantMap result) {
         // FIXME: to remain backwards-compatible the signature here is "callback(data, n/a)"
@@ -196,6 +199,7 @@ void AssetScriptingInterface::getMapping(QString asset, const ScriptValue& callb
     JS_VERIFY(AssetUtils::isValidFilePath(path), "invalid ATP file path: " + asset + "(path:"+path+")");
     JS_VERIFY(callback.isFunction(), "expected second parameter to be a callback function");
     Promise promise = getAssetInfo(path);
+    Q_ASSERT(engine);
     auto scriptEngine = engine();
     promise->ready([=](QString error, QVariantMap result) {
         jsCallback(handler, scriptEngine->newValue(error), scriptEngine->newValue(result.value("hash").toString()));
@@ -229,6 +233,7 @@ Promise AssetScriptingInterface::jsPromiseReady(Promise promise, const ScriptVal
     if (!jsVerify(handler.isValid(), "jsPromiseReady -- invalid callback handler")) {
         return nullptr;
     }
+    Q_ASSERT(engine);
     auto scriptEngine = engine();
     return promise->ready([this, handler, scriptEngine](QString error, QVariantMap result) {
         jsCallback(handler, scriptEngine->newValue(error), result);
@@ -238,6 +243,7 @@ Promise AssetScriptingInterface::jsPromiseReady(Promise promise, const ScriptVal
 void AssetScriptingInterface::jsCallback(const ScriptValue& handler,
                                          const ScriptValue& error, const ScriptValue& result) {
     Q_ASSERT(thread() == QThread::currentThread());
+    Q_ASSERT(engine);
     auto errorValue = !error.toBool() ? engine()->nullValue() : error;
     JS_VERIFY(handler.isObject() && handler.property("callback").isFunction(),
               QString("jsCallback -- .callback is not a function (%1)")
@@ -536,6 +542,7 @@ void AssetScriptingInterface::loadFromCache(const ScriptValue& options, const Sc
 }
 
 bool AssetScriptingInterface::canWriteCacheValue(const QUrl& url) {
+    Q_ASSERT(engine);
     auto scriptManager = engine()->manager();
     if (!scriptManager) {
         return false;

libraries/script-engine/src/ConsoleScriptingInterface.cpp

@@ -80,12 +80,14 @@ ScriptValue ConsoleScriptingInterface::exception(ScriptContext* context, ScriptE
 void ConsoleScriptingInterface::time(QString labelName) {
     _timerDetails.insert(labelName, QDateTime::currentDateTime().toUTC());
     QString message = QString("%1: Timer started").arg(labelName);
+    Q_ASSERT(engine);
     if (ScriptManager* scriptManager = engine()->manager()) {
         scriptManager->scriptPrintedMessage(message);
     }
 }
 
 void ConsoleScriptingInterface::timeEnd(QString labelName) {
+    Q_ASSERT(engine);
     if (ScriptManager* scriptManager = engine()->manager()) {
         if (!_timerDetails.contains(labelName)) {
             scriptManager->scriptErrorMessage("No such label found " + labelName);
@@ -134,6 +136,7 @@ ScriptValue ConsoleScriptingInterface::assertion(ScriptContext* context, ScriptE
 }
 
 void ConsoleScriptingInterface::trace() {
+    Q_ASSERT(engine);
     ScriptEnginePointer scriptEngine = engine();
     if (ScriptManager* scriptManager = scriptEngine->manager()) {
         scriptManager->scriptPrintedMessage
@@ -143,6 +146,7 @@ void ConsoleScriptingInterface::trace() {
 }
 
 void ConsoleScriptingInterface::clear() {
+    Q_ASSERT(engine);
     if (ScriptManager* scriptManager = engine()->manager()) {
         scriptManager->clearDebugLogWindow();
     }

libraries/script-engine/src/Mat4.cpp

@@ -88,6 +88,7 @@ void Mat4::print(const QString& label, const glm::mat4& m, bool transpose) const
     QString message = QString("%1 %2").arg(qPrintable(label));
     message = message.arg(glm::to_string(out).c_str());
     qCDebug(scriptengine) << message;
+    Q_ASSERT(engine);
     if (ScriptManager* scriptManager = engine()->manager()) {
         scriptManager->print(message);
     }

libraries/script-engine/src/Quat.cpp

@@ -124,6 +124,7 @@ void Quat::print(const QString& label, const glm::quat& q, bool asDegrees) {
         message = message.arg(glm::to_string(glm::dquat(q)).c_str());
     }
     qCDebug(scriptengine) << message;
+    Q_ASSERT(engine);
     if (ScriptManager* scriptManager = engine()->manager()) {
         scriptManager->print(message);
     }

libraries/script-engine/src/ScriptUUID.cpp

@@ -43,6 +43,7 @@ void ScriptUUID::print(const QString& label, const QUuid& id) {
     QString message = QString("%1 %2").arg(qPrintable(label));
     message = message.arg(id.toString());
     qCDebug(scriptengine) << message;
+    Q_ASSERT(engine);
     if (ScriptManager* scriptManager = engine()->manager()) {
         scriptManager->print(message);
     }

libraries/script-engine/src/Vec3.cpp

@@ -37,6 +37,7 @@ void Vec3::print(const QString& label, const glm::vec3& v) {
     QString message = QString("%1 %2").arg(qPrintable(label));
     message = message.arg(glm::to_string(glm::dvec3(v)).c_str());
     qCDebug(scriptengine) << message;
+    Q_ASSERT(engine);
     if (ScriptManager* scriptManager = engine()->manager()) {
         scriptManager->print(message);
     }

libraries/script-engine/src/v8/ScriptEngineV8.cpp

@@ -427,7 +427,6 @@ ScriptEngineV8::ScriptEngineV8(ScriptManager* scriptManager) :
         v8::Context::Scope contextScope(context);
         _contexts.append(std::make_shared<ScriptContextV8Wrapper>(this,context, ScriptContextPointer()));
 
-
         V8ScriptValue nullScriptValue(this, v8::Null(_v8Isolate));
         _nullValue = ScriptValue(new ScriptValueV8Wrapper(this, nullScriptValue));
 
@@ -802,6 +801,32 @@ const v8::Local<v8::Context> ScriptEngineV8::getConstContext() const {
     Q_ASSERT(!_contexts.isEmpty());
     return handleScope.Escape(_contexts.last().get()->toV8Value());
 }
+
+// Stored objects are used to create global objects for evaluateInClosure
+void ScriptEngineV8::storeGlobalObjectContents() {
+    if (areGlobalObjectContentsStored) {
+        return;
+    }
+    v8::Locker locker(_v8Isolate);
+    v8::Isolate::Scope isolateScope(_v8Isolate);
+    v8::HandleScope handleScope(_v8Isolate);
+    auto context = getContext();
+    v8::Context::Scope contextScope(context);
+    v8::Local<v8::Object> globalMemberObjects = v8::Object::New(_v8Isolate);
+
+    auto globalMemberNames = context->Global()->GetPropertyNames(context).ToLocalChecked();
+    for (size_t i = 0; i < globalMemberNames->Length(); i++) {
+        auto name = globalMemberNames->Get(context, i).ToLocalChecked();
+        if(!globalMemberObjects->Set(context, name, context->Global()->Get(context, name).ToLocalChecked()).FromMaybe(false)) {
+            Q_ASSERT(false);
+        }
+    }
+
+    _globalObjectContents.Reset(_v8Isolate, globalMemberObjects);
+    qDebug() << "ScriptEngineV8::storeGlobalObjectContents: " << globalMemberNames->Length() << " objects stored";
+    areGlobalObjectContentsStored = true;
+}
+
 ScriptValue ScriptEngineV8::evaluateInClosure(const ScriptValue& _closure,
                                                            const ScriptProgramPointer& _program) {
     PROFILE_RANGE(script, "evaluateInClosure");
@@ -812,6 +837,7 @@ ScriptValue ScriptEngineV8::evaluateInClosure(const ScriptValue& _closure,
     v8::Locker locker(_v8Isolate);
     v8::Isolate::Scope isolateScope(_v8Isolate);
     v8::HandleScope handleScope(_v8Isolate);
+    storeGlobalObjectContents();
 
     v8::Local<v8::Object> closureObject;
     //v8::Local<v8::Value> oldGlobal;
@@ -896,6 +922,7 @@ ScriptValue ScriptEngineV8::evaluateInClosure(const ScriptValue& _closure,
         if (!unwrappedProgram->compile()) {
             qDebug(scriptengine) << "Can't compile script for evaluating in closure";
             Q_ASSERT(false);
+            popContext();
             return nullValue();
         }
         const V8ScriptProgram& program = unwrappedProgram->toV8Value();
@@ -928,18 +955,35 @@ ScriptValue ScriptEngineV8::evaluateInClosure(const ScriptValue& _closure,
         {
             v8::TryCatch tryCatch(getIsolate());
             // Since V8 cannot use arbitrary object as global object, objects from main global need to be copied to closure's global object
-            auto oldGlobalMemberNames = oldContext->Global()->GetPropertyNames(oldContext).ToLocalChecked();
+            auto globalObjectContents = _globalObjectContents.Get(_v8Isolate);
-            for (size_t i = 0; i < oldGlobalMemberNames->Length(); i++) {
+            auto globalMemberNames = globalObjectContents->GetPropertyNames(globalObjectContents->CreationContext()).ToLocalChecked();
-                auto name = oldGlobalMemberNames->Get(closureContext, i).ToLocalChecked();
+            for (size_t i = 0; i < globalMemberNames->Length(); i++) {
-                if(!closureContext->Global()->Set(closureContext, name, oldContext->Global()->Get(oldContext, name).ToLocalChecked()).FromMaybe(false)) {
+                auto name = globalMemberNames->Get(closureContext, i).ToLocalChecked();
+                if(!closureContext->Global()->Set(closureContext, name, globalObjectContents->Get(globalObjectContents->CreationContext(), name).ToLocalChecked()).FromMaybe(false)) {
                     Q_ASSERT(false);
                 }
             }
+            qDebug() << "ScriptEngineV8::evaluateInClosure: " << globalMemberNames->Length() << " objects added to global";
+
+            /*auto oldGlobalMemberNames = oldContext->Global()->GetPropertyNames(oldContext).ToLocalChecked();
+            //auto oldGlobalMemberNames = oldContext->Global()->GetPropertyNames(closureContext).ToLocalChecked();
+            for (size_t i = 0; i < oldGlobalMemberNames->Length(); i++) {
+                auto name = oldGlobalMemberNames->Get(closureContext, i).ToLocalChecked();
+                //auto name = oldGlobalMemberNames->Get(oldContext, i).ToLocalChecked();
+                if(!closureContext->Global()->Set(closureContext, name, oldContext->Global()->Get(oldContext, name).ToLocalChecked()).FromMaybe(false)) {
+                //if(!closureContext->Global()->Set(closureContext, name, oldContext->Global()->Get(closureContext, name).ToLocalChecked()).FromMaybe(false)) {
+                    Q_ASSERT(false);
+                }
+            }*/
             // Objects from closure need to be copied to global object too
+            // V8TODO: I'm not sure which context to use with Get
             auto closureMemberNames = closureObject->GetPropertyNames(closureContext).ToLocalChecked();
+            //auto closureMemberNames = closureObject->GetPropertyNames(oldContext).ToLocalChecked();
             for (size_t i = 0; i < closureMemberNames->Length(); i++) {
                 auto name = closureMemberNames->Get(closureContext, i).ToLocalChecked();
+                //auto name = closureMemberNames->Get(oldContext, i).ToLocalChecked();
                 if(!closureContext->Global()->Set(closureContext, name, closureObject->Get(closureContext, name).ToLocalChecked()).FromMaybe(false)) {
+                //if(!closureContext->Global()->Set(closureContext, name, closureObject->Get(oldContext, name).ToLocalChecked()).FromMaybe(false)) {
                     Q_ASSERT(false);
                 }
             }
@@ -1455,6 +1499,7 @@ ScriptContext* ScriptEngineV8::currentContext() const {
         // I'm not sure how to do this without discarding const
         _currContext = std::make_shared<ScriptContextV8Wrapper>(const_cast<ScriptEngineV8*>(this));
     }*/
+    // V8TODO: add FunctionCallbackInfo or PropertyCallbackInfo when necessary
     return _contexts.last().get();
 }
 
@@ -1501,7 +1546,7 @@ ScriptValue ScriptEngineV8::newFunction(ScriptEngine::FunctionSignature fun, int
         ScriptEngineV8 *scriptEngine = reinterpret_cast<ScriptEngineV8*>
             (object->GetAlignedPointerFromInternalField(1));
         ScriptContextV8Wrapper scriptContext(scriptEngine, &info, scriptEngine->getContext(), scriptEngine->currentContext()->parentContext());
-        //V8TODO: this scriptContext needs to have FunctionCallbackInfo added
+        ScriptContextGuard scriptContextGuard(&scriptContext);
         ScriptValue result = function(&scriptContext, scriptEngine);
         ScriptValueV8Wrapper* unwrapped = ScriptValueV8Wrapper::unwrap(result);
         if (unwrapped) {

libraries/script-engine/src/v8/ScriptEngineV8.h

@@ -202,6 +202,8 @@ public: // not for public use, but I don't like how Qt strings this along with p
 
     ScriptContextV8Pointer pushContext(v8::Local<v8::Context> context);
     void popContext();
+    // V8TODO: call this after initializing global object
+    void storeGlobalObjectContents();
 
 protected:
     // like `newFunction`, but allows mapping inline C++ lambdas with captures as callable V8ScriptValues
@@ -240,6 +242,8 @@ protected:
     //mutable ScriptContextV8Pointer _currContext;
     // Current context stack. Main context is first on the list and current one is last.
     QList<ScriptContextV8Pointer> _contexts;
+    v8::Persistent<v8::Object> _globalObjectContents;
+    bool areGlobalObjectContentsStored {false};
 
     //V8TODO
     //ArrayBufferClass* _arrayBufferClass;

libraries/script-engine/src/v8/ScriptObjectV8Proxy.cpp

@@ -39,9 +39,9 @@ static const void *internalPointsToMethodProxy = (void *)0x13373000;
 
 // Used strictly to replace the "this" object value for property access.  May expand to a full context element
 // if we find it necessary to, but hopefully not needed
-class ScriptPropertyContextQtWrapper final : public ScriptContext {
+class ScriptPropertyContextV8Wrapper final : public ScriptContext {
 public:  // construction
-    inline ScriptPropertyContextQtWrapper(const ScriptValue& object, ScriptContext* parentContext) :
+    inline ScriptPropertyContextV8Wrapper(const ScriptValue& object, ScriptContext* parentContext) :
         _parent(parentContext), _object(object) {}
 
 public:  // ScriptContext implementation
@@ -568,7 +568,7 @@ V8ScriptValue ScriptObjectV8Proxy::property(const V8ScriptValue& object, const V
 
             QMetaProperty prop = metaObject->property(propId);
             ScriptValue scriptThis = ScriptValue(new ScriptValueV8Wrapper(_engine, object));
-            ScriptPropertyContextQtWrapper ourContext(scriptThis, _engine->currentContext());
+            ScriptPropertyContextV8Wrapper ourContext(scriptThis, _engine->currentContext());
             ScriptContextGuard guard(&ourContext);
 
             QVariant varValue = prop.read(qobject);
@@ -611,7 +611,7 @@ V8ScriptValue ScriptObjectV8Proxy::property(const V8ScriptValue& object, const V
             ScriptEngine::QObjectWrapOptions options = ScriptEngine::ExcludeSuperClassContents |
                                                         //V8TODO ScriptEngine::ExcludeDeleteLater |
                                                         ScriptEngine::PreferExistingWrapperObject;
-            //V8TODO: why is it returning new object every time?
+            // It's not necessarily new, newQObject looks for it first in object wrapper map
             return ScriptObjectV8Proxy::newQObject(_engine, proxy, ScriptEngine::ScriptOwnership, options);
             //return _engine->newQObject(proxy, ScriptEngine::ScriptOwnership, options);
         }
@@ -642,7 +642,7 @@ void ScriptObjectV8Proxy::setProperty(V8ScriptValue& object, const V8ScriptStrin
     QMetaProperty prop = metaObject->property(propId);
 
     ScriptValue scriptThis = ScriptValue(new ScriptValueV8Wrapper(_engine, object));
-    ScriptPropertyContextQtWrapper ourContext(scriptThis, _engine->currentContext());
+    ScriptPropertyContextV8Wrapper ourContext(scriptThis, _engine->currentContext());
     ScriptContextGuard guard(&ourContext);
 
     int propTypeId = prop.userType();
@@ -883,8 +883,10 @@ void ScriptMethodV8Proxy::call(const v8::FunctionCallbackInfo<v8::Value>& argume
     }
 
     if (isValidMetaSelected) {
-        //ScriptContextV8Wrapper ourContext(_engine, context);
+        // V8TODO: is this the correct wrapper?
-        //ScriptContextGuard guard(&ourContext);
+        ScriptContextV8Wrapper ourContext(_engine, &arguments, _engine->getContext(),
+                                          _engine->currentContext()->parentContext());
+        ScriptContextGuard guard(&ourContext);
         const QMetaMethod& meta = _metas[bestMeta];
         int returnTypeId = meta.returnType();
         QVector <QGenericArgument> &qGenArgs = qGenArgsVectors[bestMeta];
@@ -1333,8 +1335,15 @@ void ScriptSignalV8Proxy::connect(ScriptValue arg0, ScriptValue arg1) {
     v8::Local<v8::Function> destFunction = v8::Local<v8::Function>::Cast(callback.get());
     v8::Local<v8::String> destDataName = v8::String::NewFromUtf8(isolate, "__data__").ToLocalChecked();
     v8::Local<v8::Value> destData;
-    auto destFunctionContext = destFunction->CreationContext();
+    // V8TODO: I'm not sure which context to use here
+    //auto destFunctionContext = destFunction->CreationContext();
+    auto destFunctionContext = _engine->getContext();
+    Q_ASSERT(thisObject().isObject());
     V8ScriptValue v8ThisObject = ScriptValueV8Wrapper::fullUnwrap(_engine, thisObject());
+    Q_ASSERT(ScriptObjectV8Proxy::unwrapProxy(v8ThisObject));
+    ScriptSignalV8Proxy* thisProxy = dynamic_cast<ScriptSignalV8Proxy*>(ScriptObjectV8Proxy::unwrapProxy(v8ThisObject)->toQObject());
+    Q_ASSERT(thisProxy);
+    qDebug(scriptengine) << "ScriptSignalV8Proxy::connect: " << thisProxy->fullName() << " fullName: " << fullName();
     //Q_ASSERT(destFunction->InternalFieldCount() == 4);
     //Q_ASSERT(destData.get()->IsArray());
     //v8::Local<v8::Value> destData = destFunction->GetInternalField(3);
@@ -1344,15 +1353,27 @@ void ScriptSignalV8Proxy::connect(ScriptValue arg0, ScriptValue arg1) {
     if (destData->IsArray()) {
         v8::Local<v8::Array> destArray = v8::Local<v8::Array>::Cast(destData);
         int length = destArray->Length();//destData.property("length").toInteger();
+        // V8TODO: Maybe copying array is unnecessary?
         v8::Local<v8::Array> newArray = v8::Array::New(isolate, length + 1);
         bool foundIt = false;
         for (int idx = 0; idx < length && !foundIt; ++idx) {
             v8::Local<v8::Value> entry = destArray->Get(destFunctionContext, idx).ToLocalChecked();
+            {
+                qDebug() << "ScriptSignalV8Proxy::connect: entry details: " << _engine->scriptValueDebugDetailsV8(V8ScriptValue(_engine, entry));
+                Q_ASSERT(entry->IsObject());
+                V8ScriptValue v8EntryObject(_engine, entry);
+                Q_ASSERT(ScriptObjectV8Proxy::unwrapProxy(v8EntryObject));
+                // For debugging
+                ScriptSignalV8Proxy* entryProxy = dynamic_cast<ScriptSignalV8Proxy*>(ScriptObjectV8Proxy::unwrapProxy(v8EntryObject)->toQObject());
+                Q_ASSERT(thisProxy);
+                qDebug(scriptengine) << "ScriptSignalV8Proxy::connect: entry proxy: " << entryProxy->fullName();
+            }
             if (!newArray->Set(destFunctionContext, idx, entry).FromMaybe(false)) {
                 Q_ASSERT(false);
             }
         }
         if (!newArray->Set(destFunctionContext, length, v8ThisObject.get()).FromMaybe(false)) {
+        //if (!newArray->Set(destFunctionContext, length, v8ThisObject.get()).FromMaybe(false)) {
             Q_ASSERT(false);
         }
         if (!destFunction->Set(destFunctionContext, destDataName, newArray).FromMaybe(false)) {
@@ -1448,8 +1469,16 @@ void ScriptSignalV8Proxy::disconnect(ScriptValue arg0, ScriptValue arg1) {
     v8::Local<v8::Function> destFunction = v8::Local<v8::Function>::Cast(callback.get());
     v8::Local<v8::String> destDataName = v8::String::NewFromUtf8(isolate, "__data__").ToLocalChecked();
     v8::Local<v8::Value> destData;
-    auto destFunctionContext = destFunction->CreationContext();
+
+    //auto destFunctionContext = destFunction->CreationContext();
+    auto destFunctionContext = _engine->getContext();
+    Q_ASSERT(thisObject().isObject());
     V8ScriptValue v8ThisObject = ScriptValueV8Wrapper::fullUnwrap(_engine, thisObject());
+    Q_ASSERT(ScriptObjectV8Proxy::unwrapProxy(v8ThisObject));
+    // For debugging
+    ScriptSignalV8Proxy* thisProxy = dynamic_cast<ScriptSignalV8Proxy*>(ScriptObjectV8Proxy::unwrapProxy(v8ThisObject)->toQObject());
+    Q_ASSERT(thisProxy);
+    qDebug(scriptengine) << "ScriptSignalV8Proxy::disconnect: " << thisProxy->fullName() << " fullName: " << fullName();
     //V8ScriptValue destData = callback.data();
     //Q_ASSERT(destData->IsArray());
     if (!destFunction->Get(destFunctionContext, destDataName).ToLocal(&destData)) {
@@ -1463,8 +1492,22 @@ void ScriptSignalV8Proxy::disconnect(ScriptValue arg0, ScriptValue arg1) {
         int newIndex = 0;
         for (int idx = 0; idx < length && !foundIt; ++idx) {
             v8::Local<v8::Value> entry = destArray->Get(destFunctionContext, idx).ToLocalChecked();
+            // For debugging:
+            {
+                _engine->logBacktrace("ScriptSignalV8Proxy::disconnect");
+                qDebug() << "ScriptSignalV8Proxy::disconnect: entry details: " << _engine->scriptValueDebugDetailsV8(V8ScriptValue(_engine, entry));
+                Q_ASSERT(entry->IsObject());
+                V8ScriptValue v8EntryObject(_engine, entry);
+                Q_ASSERT(ScriptObjectV8Proxy::unwrapProxy(v8EntryObject));
+                // For debugging
+                ScriptSignalV8Proxy* entryProxy = dynamic_cast<ScriptSignalV8Proxy*>(ScriptObjectV8Proxy::unwrapProxy(v8EntryObject)->toQObject());
+                Q_ASSERT(thisProxy);
+                qDebug(scriptengine) << "ScriptSignalV8Proxy::disconnect: entry proxy: " << entryProxy->fullName();
+            }
             if (entry->StrictEquals(v8ThisObject.get())) {
+                //V8TODO: compare proxies instead?
                 foundIt = true;
+                qDebug() << "ScriptSignalV8Proxy::disconnect foundIt";
                 //V8ScriptValueList args;
                 //args << idx << 1;
                 //destData.property("splice").call(destData, args);

libraries/script-engine/src/v8/ScriptObjectV8Proxy.h

@@ -235,12 +235,14 @@ private:  // implementation
     virtual int qt_metacall(QMetaObject::Call call, int id, void** arguments) override;
     int discoverMetaCallIdx();
     ConnectionList::iterator findConnection(V8ScriptValue thisObject, V8ScriptValue callback);
-    QString fullName() const;
+    //QString fullName() const;
 
 public:  // API
     // arg1 was had Null default value, but that needs isolate pointer to create Null in V8
     virtual void connect(ScriptValue arg0, ScriptValue arg1 = ScriptValue()) override;
     virtual void disconnect(ScriptValue arg0, ScriptValue arg1 = ScriptValue()) override;
+    //Moved to public temporarily for debugging:
+    QString fullName() const;
 
     //virtual void connect(V8ScriptValue arg0) override;
     //virtual void disconnect(V8ScriptValue arg0) override;

plugins/JSAPIExample/src/JSAPIExample.cpp

@@ -162,6 +162,7 @@ namespace REPLACE_ME_WITH_UNIQUE_NAME {
           * settings = null; // optional best pratice; allows the object to be reclaimed ASAP by the JS garbage collector
           */
         ScriptValue getScopedSettings(const QString& scope) {
+            Q_ASSERT(engine);
             auto engine = Scriptable::engine();
             if (!engine) {
                 return ScriptValue();